The average energy density of the macroscopic quasimonochromatic electromagnetic field \U0001d4b0ts(t,r) in a linear passive chiral lossy medium described by the constitutive E–H relations is determined using a microscopic model. According to the model, \U0001d4b0ts(t,r) is equal to the sum of the average energy densities of the electromagnetic field in free space \U0001d4b0t0(t,r) and electromagnetic oscillations in structural elements \U0001d4b0s(t,r) induced by the electromagnetic wave. Making use of the Poynting theorem, the energy density and power density of losses are derived as functions of the Poynting vector, polarization of the electromagnetic waves, phase shift between the field vectors and refractive index of a chiral medium. The exact energy velocity of the quasimonochromatic electromagnetic waves satisfying relativistic causality is determined using \U0001d4b0ts(t,r). The approximate energy velocities of the quasimonochromatic electromagnetic wave are determined using energy density components approximating \U0001d4b0ts(t,r) (e.g., the sum of the positive energy densities of the macroscopic electric and magnetic fields as well as the energy density of magnetoelectric cross-coupling). Comparison of the exact and approximate energy velocities with the group velocity in the case of a chiral lossy medium with a single-resonant frequency clarifies the concept of the electromagnetic energy and demonstrates the fundamental significance of the exact energy velocity.